Inflammatory profile discriminates clinical subtypes in LRRK2-associated Parkinson's disease.

BACKGROUND AND PURPOSE: The presentation of Parkinson's disease patients with mutations in the LRRK2 gene (PDLRRK2 ) is highly variable, suggesting a strong influence of modifying factors. In this context, inflammation is a potential candidate inducing clinical subtypes. METHODS: An extensive battery of peripheral inflammatory markers was measured in human serum in a multicentre cohort of 142 PDLRRK2 patients from the MJFF LRRK2 Consortium, stratified by three different subtypes as recently proposed for idiopathic Parkinson's disease: diffuse/malignant, intermediate and mainly pure motor. RESULTS: Patients classified as diffuse/malignant presented with the highest levels of the pro-inflammatory proteins interleukin 8 (IL-8), monocyte chemotactic protein 1 (MCP-1) and macrophage inflammatory protein 1-ß (MIP-1-ß) paralleled by high levels of the neurotrophic protein brain-derived neurotrophic factor (BDNF). It was also possible to distinguish the clinical subtypes based on their inflammatory profile by using discriminant and area under the receiver operating characteristic curve analysis. CONCLUSIONS: Inflammation seems to be associated with the presence of a specific clinical subtype in PDLRRK2 that is characterized by a broad and more severely affected spectrum of motor and non-motor symptoms. The pro-inflammatory metabolites IL-8, MCP-1 and MIP-1-ß as well as BDNF are interesting candidates to be included in biomarker panels that aim to differentiate subtypes in PDLRRK2 and predict progression.

Monochorial diamniotic dizygotic twins in a German Shepherd Dog: A case report.

CASE REPORT: A 6.5-year-old clinically healthy German Shepherd Dog with regular oestrous cycles of 6 months was presented for pregnancy diagnosis on day 38 after ovulation (p.ov.). Ultrasonography revealed three individual placental sites in progressed resorption and two vital adequately developed foetuses sharing a joint placenta. On days 41 and 48 p.ov., sonographic signs indicated normal development of both foetuses, but on day 52 p.ov., both foetuses were found to be dead. A caesarean section was performed the same day. Examination of the removed uterus confirmed the diagnosis of a "twin" pregnancy with two foetuses sharing the same placental site but separate amniotic membranes. One foetus showed generalized oedema (anasarca). Bacterial culture of swabs taken from inside the placental cavity was negative. At histological examination of the uterus, no signs of inflammation were found. Serum relaxin concentrations (day 38, 41, 48 and 52. p.ov.) were consistent with those of bitches with normal pregnancies. Cytogenetic analysis of the two foetuses revealed dizygotic twins, one male and one female according to SRY-PCR. By genotyping 17 high-polymorphic canine microsatellites, it could be demonstrated that the two foetuses developed from two different oocytes.

Effect of short-term scrotal hyperthermia on spermatological parameters, testicular blood flow and gonadal tissue in dogs.

The objective was to assess the effect of a short-term scrotal hyperthermia in dogs on quantitative and qualitative ejaculate parameters, testicular blood flow and testicular and epididymal histology. After a control period, the scrotum of seven normospermic adult beagle dogs was insulated with a self-made suspensory for 48 h. Nine weeks later, two animals were castrated, while in five animals, scrotal hyperthermia was repeated. Dogs were castrated either 10 or 40 days thereafter. In each phase of scrotal insulation, average scrotal surface temperature increased by 3.0°C. Semen was collected twice weekly throughout the experiment. Total sperm count did not change after the first hyperthermia, but it slightly decreased after the second (p < 0.05). Profiles of sperm morphology and velocity parameters (CASA) rather indicated subtle physiological variations in sperm quality than effects of a local heat stress. Chromatin stability of ejaculated spermatozoa as indicated by SCSA remained constant throughout the experiment. Perfusion characteristics of the gonads, that is, systolic peak velocity, pulsatility and resistance index at the marginal location of the testicular artery, did not change due to hyperthermia (p > 0.05). Histological examination of excised testes and epididymides for apoptotic (TUNEL and activated caspase-3) and proliferating cells (Ki-67 antigen) indicated only marginal effects of scrotal insulation on tissue morphology. In conclusion, a mild short-term scrotal hyperthermia in dogs does not cause substantial changes in sperm quantity and quality. In contrast to other species, canine testes and epididymides may have a higher competence to compensate such thermal stress.

Serum progesterone in pregnant bitches supplemented with progestin because of expected or suspected luteal insufficiency.

Progesterone profiles of individual bitches may vary considerably both between and within individuals during pregnancy and non-pregnancy. Suspected luteal deficiency is commonly purported but is difficult to evaluate in clinical cases when progesterone is supplemented because this masks the underlying hormone changes. Therefore, in this study, suspected cases of luteal deficiency (six pregnancies from five bitches) were supplemented with oral medroxyprogesterone acetate (MPA), allowing measurement of endogenous progesterone using conventional assay. MPA (0.1 mg/kg) treatment commenced between days 30 and 36 after estimated ovulation and was continued for 18-28 days. Endogenous progesterone was measured throughout treatment, and blood was additionally analysed for prolactin (PRL) and relaxin (RLN) as well as MPA. The latter revealed delayed MPA clearance in two bitches, in which Caesarean operation had to be performed because of a low foetal heart rate. In two cases with confirmed basal concentrations of both P(4) and MPA at term, spontaneous parturition occurred. Low endogenous progesterone during pregnancy was not apparent in three bitches that had previously had a short inter-oestrous interval of which two had previously had confirmed short luteal phase. However, in the remaining two cases, there had been previous pregnancy failure, but in only one of these, a premature decrease in endogenous progesterone to <2 ng/ml was detected. The latter had also low concentrations of PRL and RLN. The results of this preliminary clinical study suggest that abnormal progesterone profiles in pregnancy may be uncommon in bitches even when there has been previously documented short inter-oestrous interval. However, luteal deficiency may be suspected in bitches with a history of repeated pregnancy failure or abortion. MPA supplementation appears to be efficacious for management of suspected luteal deficiency and verification of the ovarian dysfunction, but care should be taken regarding the timing of MPA withdrawal and prolongation of pregnancy because of delayed elimination of MPA from blood circulation.

Testicular steroids, prolactin, relaxin and prostate gland markers in peripheral blood and seminal plasma of normal dogs and dogs with prostatic hyperplasia.

Concentrations of 17ß-oestradiol (E(2) ), testosterone (T), 5α-dihydrotestosterone, prolactin (PRL) and relaxin (RLN) were determined in peripheral blood serum or plasma and prostatic secretion of 77 physically healthy intact male dogs (19 Rhodesian Ridgebacks/RR, 58 dogs of other breeds, 1-9 years of age). Furthermore, the concentrations of acid phosphatase in prostatic secretion and canine prostate-specific esterase (CPSE) were measured in blood plasma. All dogs were submitted to a complete breeding soundness examination, including B-mode sonography. Prostatic volume was larger, and blood plasma levels of CPSE were higher in ageing dogs and in dogs with benign prostatic hyperplasia (BPH) compared with young dogs and dogs with normal prostate. Furthermore, a higher E(2) /T ratio was found in dogs with BPH. Despite missing significant differences in PRL concentrations, the slight increases in PRL concentrations in the prostatic secretion observed both with increasing age and in dogs with BPH and the observed correlations between concentrations of PRL and testicular steroids may possibly indicate a role of PRL in the pathogenesis of canine BPH. Serum RLN concentrations were at similar level in all dogs. Regarding breed differences, an appreciably larger prostatic volume and higher concentration of CPSE were verified in RR than in other pure-bred dogs, confirming our suspicion of a premature enlargement of the prostate gland, which may result from a genetic disposition for BPH in this breed.

Sulforaphane targets pancreatic tumour-initiating cells by NF-kappaB-induced antiapoptotic signalling.

BACKGROUND AND AIMS: Emerging evidence suggests that highly treatment-resistant tumour-initiating cells (TICs) play a central role in the pathogenesis of pancreatic cancer. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered to be a novel anticancer agent; however, recent studies have shown that many pancreatic cancer cells are resistant to apoptosis induction by TRAIL due to TRAIL-activated nuclear factor-kappaB (NF-kappaB) signalling. Several chemopreventive agents are able to inhibit NF-kappaB, and favourable results have been obtained--for example, for the broccoli compound sulforaphane-in preventing metastasis in clinical studies. The aim of the study was to identify TICs in pancreatic carcinoma for analysis of resistance mechanisms and for definition of sensitising agents. METHODS: TICs were defined by expression patterns of a CD44(+)/CD24(-), CD44(+)/CD24(+) or CD44(+)/CD133(+) phenotype and correlation to growth in immunodeficient mice, differentiation grade, clonogenic growth, sphere formation, aldehyde dehydrogenase (ALDH) activity and therapy resistance. RESULTS: Mechanistically, specific binding of transcriptionally active cRel-containing NF-kappaB complexes in TICs was observed. Sulforaphane prevented NF-kappaB binding, downregulated apoptosis inhibitors and induced apoptosis, together with prevention of clonogenicity. Gemcitabine, the chemopreventive agents resveratrol and wogonin, and the death ligand TRAIL were less effective. In a xenograft model, sulforaphane strongly blocked tumour growth and angiogenesis, while combination with TRAIL had an additive effect without obvious cytotoxicity in normal cells. Freshly isolated patient tumour cells expressing markers for TICs could be sensitised by sulforaphane for TRAIL-induced cytotoxicity. CONCLUSION: The data provide new insights into resistance mechanisms of TICs and suggest the combination of sulforaphane with TRAIL as a promising strategy for targeting of pancreatic TICs.

Effects of gonadectomy on prolactin and LH secretion and the pituitary-thyroid axis in male dogs.

The effects of gonadectomy on the secretion of prolactin, LH, TSH, and thyroxine were investigated. Blood serum hormone concentrations were analysed before and at 20, 120, and 180min after a single iv TRH injection in each of eight healthy intact and castrated male beagle dogs before (control) and after 4-week treatment with the dopamine-2 receptor agonist cabergoline. Under control conditions the mean prolactin, TSH, and thyroxine concentrations were similar in intact and gonadectomised dogs, and administration of TRH provoked a significant (p<0.01) increase in concentrations of the three hormones. The overall inhibitory effect of cabergoline treatment on prolactin secretion was more pronounced in the castrated dogs compared with the intact group. Cabergoline significantly suppressed the TRH-induced prolactin increase in each group (p<0.01). Corresponding TRH-stimulated TSH concentrations were not affected by cabergoline. In the gonadectomised dogs, thyroxine concentrations before and at 120 and 180min after TRH injection were significantly lower than under control conditions. LH concentrations were always higher (p<0.01) in gonadectomised dogs compared with the intact dogs, but appeared to be affected neither by TRH nor by cabergoline administration. It can thus be concluded from the results, that gonadectomy does not result in hyperprolactinaemia in male dogs, while LH concentrations are significantly increased due to missing androgen feedback. Thyroid function remains unaffected by gonadectomy. Testicular steroids appear to interact with central dopaminergic and probably other neuroendocrine mechanisms regulating the secretion of prolactin, TSH, and thyroxine. Thus, long-term dopamine-2 receptor agonistic treatment may lead to a hypothyroid condition in castrated male dogs.

Comparison of selected endocrine parameters during luteal phase and pregnancy in German Shepherd dogs and Beagles.

Concentrations of progesterone, prolactin and relaxin in serum at predetermined intervals after ovulation (day 0) in non-pregnant and pregnant normocyclic Beagles were assayed and results compared with those observed in German Shepherd dogs (GSD) in a previous study. The goal was to determine possible reproductive hormone specificities related to the GSD breed. Furthermore, the effects of medroxyprogesterone acetate (MPA)-treatment in non-pregnant Beagles and of progesterone supplementation in pregnant Beagles on the hormone concentrations were examined. Mean concentrations of progesterone and prolactin were not different in the non-pregnant Beagles compared with those seen in non-pregnant GSD, except at days 50-60, when progesterone concentrations were found to be higher in Beagles (p < 0.05). Mean progesterone concentrations in pregnant Beagles at days 50-60 after ovulation (day 0) were higher (p < 0.05) than in GSD at that time, but not at earlier time periods. Prolactin concentrations were higher (p < 0.05) in Beagles throughout pregnancy compared with those in the GSD. Mean relaxin concentrations were numerically but not significantly lower in GSD than in Beagles throughout pregnancy. A 10-day oral MPA treatment did not affect progesterone or prolactin secretion in normocyclic non-pregnant Beagles. Medroxyprogesterone acetate serum concentrations were approximately 3.9 ng/ml during treatment and decreased to 0.42 and 0.021 ng/ml within 5 and 15 days after end of treatment, respectively. Intramuscular progesterone supplementation from days 30 to 40 in pregnant Beagles resulted in higher concentrations of progesterone in the 36- to 45-day time periods; prolactin and relaxin concentrations were not significantly affected during or after treatment compared with administration of placebo. The results suggest a tendency towards deficient luteal function in the short-cycle GSD bitches previously studied, which in pregnancy may reflect the observed decreased prolactin concentrations; the possibility that GSD relaxin secretion is deficiency required needs further study. As oral treatment with MPA did not affect progesterone and prolactin release, it may be useful for studying luteal function in pregnant bitches with suspected hypoluteoidism.

Morphological examination of the corpora lutea from pregnant bitches treated with different abortifacient regimes.

Different abortifacient regimes in dogs were analysed for their effect on the pregnancy corpora lutea (CL), namely, prostaglandin F2a analogue cloprostenol (CLO) combined with dopamine agonist cabergoline (CAB), or progesterone (P4) receptor antagonist aglepristone (AGL). Ovaries were collected after 6-10 days of treatment during first trimester. The CL of the control-group showed strong expression of relaxin (RLX), its receptor RXFP1 and enzymes of steroid biosynthesis (HSD) with high peripheral P4-levels. Whereas RXL, RXFP1 and HSD were lowest expressed in the CLO/CAB-group with a massive degeneration of CL and their blood vessels combined with low peripheral P4-level. The AGL-group showed less extensive CL degeneration and more intensive staining of the examined factors than CLO/CAB. In summary, all examined factors are associated with normal luteal function and are useful tools to stage luteolysis. Although both treatments have the same abortive action, their sequence of events on the CL is different.

Effects of short-term hyper- and hypoprolactinaemia on hormones of the pituitary, gonad and -thyroid axis and on semen quality in male Beagles.

Effects of a short-term hyper- and hypoprolactinaemia on serum concentrations of LH, testosterone and semen quality in six male Beagles were investigated. Blood samples were collected at 3-day intervals for 12 weeks. The time span was divided into five 3-week periods: pre-treatment, metoclopramide (MCP) treatment (0.2 mg/kg orally three times daily), cabergoline (CAB) treatment (5 microg/kg orally once daily), post-treatment 1 and post-treatment 2. In the latter, only semen characteristics were evaluated. Semen parameters were analyzed once per week during the whole 15-week investigation time. At the end of each period, the effects of a single intravenous injection of thyrotropin-releasing hormone (TRH; 10 microg/kg) on the secretion of prolactin (PRL), LH, testosterone, thyroid-stimulating hormone and thyroxine (T4) were investigated. Pre-treatment serum PRL concentration increased under MCP (p < 0.05), followed by a decrease under CAB administration (p < 0.05). Luteinizing hormone and testosterone concentrations were not affected. Except for straight-line sperm velocity, semen quality did not differ between collection periods. A single iv TRH injection induced a significant PRL increase at 20 min in all experimental periods except during CAB treatment. Luteinizing hormone and testosterone did not show clear TRH-related changes. Basic T4 levels were significantly reduced after CAB treatment (p < 0.05). The results of the present study demonstrate that MCP-induced short-term hyperprolactinaemia in male beagles does not seriously affect the hypothalamo-pituitary axis and semen quality.

Influence of progesterone withdrawal on pregnancy-related parameters during post-implantation early pregnancy loss.

Pharmacologically-induced luteolysis or treatment with an antiprogestin in early post-implantation pregnancy in dogs results in asynchronous death and resorption of conceptuses, indicating variable rates of response of individual conceptuses towards progesterone deficiency. This variability also seems to occur in bitches showing pregnancy failure in response to spontaneous luteal deficiency. In a total of 10 beagle pregnancies (two consecutive pregnancies of five bitches), abortifacient treatments beginning on day 24 after ovulation (ov) involved either administration of a progestin antagonist (total of six pregnancies, in three bitches) or a luteolytic regimen of prostaglandin F(2alpha)-analogue together with a dopamine agonist (total of four pregnancies, in two bitches). The outcomes were evaluated in relation to four control pregnancies in two bitches by assay of serum progesterone, prolactin and relaxin at selected time points or within selected time periods, by ultrasound of conceptuses including measurement of uterine blood flow, and parameters of the blood fibrinolytic system including plasma fibrinogen and plasminogen. The process of embryonic death and conceptus resorption was variable in onset and duration both in bitches that received the progesterone antagonist aglepristone (AGLE) and in those under the luteolytic treatment (cloprostenol combined with cabergoline). Pregnancy termination (death of all embryos or foetuses, respectively) occurred as early as day 29 and as late as day 41 after ov in AGLE-treated bitches, and not earlier than day 37 after ov in luteolytic-treatment bitches. Impending embryonic death was not predicted by changes in relaxin concentration, parameters of the fibrinolytic system, or in the perfusion of small uteroplacental vessels.

Concentrations of prolactin, LH, testosterone, TSH and thyroxine in normospermic dogs of different breeds.

Concentrations of prolactin (PRL), LH, testosterone (T), TSH and thyroxine (T(4)) were determined before and at 20, 120 and 180 min after a single iv injection of thyrotropin-releasing hormone (TRH) in eight Beagles, eight Fox Terriers, six Labrador Retrievers and five Great Danes that were normospermic. Mean basal PRL concentrations were lower in the Fox Terriers compared with the Great Danes (p < 0.05). Mean LH concentrations were higher in the Fox Terriers than in the Beagles, and T was lower in the Fox Terriers at some times but not others (p < 0.05). Thyroid Stimulating Hormone (TSH) concentrations did not differ among breeds, while mean basal T(4) values were lower in Fox Terriers compared with Labrador Retrievers and Great Danes (p < 0.05). Stimulation of T(4) secretion 120 and 180 min after iv TRH injection was most pronounced in the Beagles and less in the Fox Terriers (p < 0.05). The results of the present study indicate that potential breed differences in circulating concentrations of PRL, LH, T, TSH and T(4) in male dogs with apparently normal fertility can be encountered, but further studies are needed to determine whether the observed differences are typical features of these breeds, reflect subsets of dogs within breeds, or are in part because of possible uncontrolled parameters such as sample timing, ambient photoperiod, housing conditions or diet.

VEGF expression by mesenchymal stem cells contributes to angiogenesis in pancreatic carcinoma.

Little is known about the factors that enable the mobilisation of human mesenchymal stem cells (MSC) from the bone marrow into the blood stream and their recruitment to and retention in the tumour. We found specific migration of MSC towards growth factors present in pancreatic tumours, such as PDGF, EGF, VEGF and specific inhibitors Glivec, Erbitux and Avastin interfered with migration. Within a few hours, MSC migrated into spheroids consisting of pancreatic cancer cells, fibroblasts and endothelial cells as measured by time-lapse microscopy. Supernatant from subconfluent MSC increased sprouting of HUVEC due to VEGF production by MSC itself as demonstrated by RT-PCR and ELISA. Only few MSCs were differentiated into endothelial cells in vitro, whereas in vivo differentiation was not observed. Lentiviral GFP-marked MSCs, injected in nude mice xenografted with orthotopic pancreatic tumours, preferentially migrated into the tumours as observed by FACS analysis of green fluorescent cells. By immunofluorescence and intravital microscopic studies, we found the interaction of MSC with the endothelium of blood vessels. Mesenchymal stem cells supported tumour angiogenesis in vivo, that is CD31(+) vessel density was increased after the transfer of MSC compared with siVEGF-MSC. Our data demonstrate the migration of MSC toward tumour vessels and suggest a supportive role in angiogenesis.

Proliferative and apoptotic changes in the healthy canine endometrium and in cystic endometrial hyperplasia.

Proliferation and apoptosis play an important role in cyclic changes in the healthy canine endometrium. Proteins of the Bcl-2-family are known to be involved in the regulation of apoptosis. However, only few reports mention their expression patterns during cystic endometrial hyperplasia (CEH). In order to correlate proliferative and apoptotic processes, expression of the apoptosis-regulatory proteins Bcl-2 (anti-apoptotic) and Bax (pro-apoptotic) in healthy and cystic hyperplastic endometrial tissue as well as in pyometra was investigated. Uteri from 33 bitches were assigned to three groups: group 1 - healthy endometrium (n = 12), group 2 - CEH (n = 17) and group 3 - pyometra (n = 4). Markers for proliferation (Ki-67) and apoptosis (activated caspase-3 and TUNEL-method) as well as expression of Bcl-2 and Bax were determined in all endometrial layers. For groups 1 and 2 this was done during endometrial gland secretion in mid and late luteal phase (mLP, lLP), endometrial reparation in early anestrus (eAE) and in the regenerated endometrium in late anestrus (lAE). For group 3 only the late luteal phase was investigated. In group 1, cyclic proliferation patterns were found predominantly in superficial glands (SG) and stroma, whereas progesterone-mediated low expression levels coincided with high apoptosis rates in the basal glands (BG). In eAE, higher apoptotic activity was detected compared to lLP and lAE. Bcl-2 and Bax expression levels showed an inverse cyclic relationship in all tissue layers. In the stroma, in eAE, a rise in proliferative activity and concomitant increase in anti-apoptotic Bcl-2 expression levels was found, indicating that this layer serves as a source for endometrial regeneration. In CEH, no or limited cyclic patterns of proliferation, apoptosis, Bcl-2 and Bax were found. Increased proliferation rates coincided with deregulated apoptosis. Besides the glandular compartments, the stroma played an important role in the pathogenesis of canine CEH. In case of pyometra, both proliferation and apoptosis increased, indicating irreversible damage of the inflamed canine endometrium. In conclusion Bcl-2 and Bax play a role both in the physiological regenerative processes of the cyclic canine endometrium and in deregulating proliferation and apoptosis in CEH and pyometra.

Complementary and alternative medicine and coping in neuroimmunological diseases.

The utilisation of complementary and alternative medicine (CAM) is widespread in neuroimmunological diseases like multiple sclerosis (MS) but has been disregarded in research until lately. After describing the problems of definition in CAM, different categories will be described. Various confounding factors on CAM utilisation exist, though hardly investigated. Besides sociodemographic variables like education, income, gender and age, illness-related factors like severity of disease are discussed. Furthermore, the important role of coping and CAM utilisation has not been investigated in neuroimmunological diseases, yet. Results derived from our investigations on CAM utilisation in MS indicate that users of CAM apply coping strategies, such as "rumination", "search for information" and "search for meaning in religion", more frequently than non-users and that current CAM utilisation is related to depression. Further research is needed in this field, as well as in other neuroimmunological diseases.

MUC1 inhibition leads to decrease in PD-L1 levels via upregulation of miRNAs.

The PD-L1/PD-1 pathway is a critical component of the immunosuppressive tumor microenvironment in acute myeloid leukemia (AML), but little is known about its regulation. We investigated the role of the MUC1 oncoprotein in modulating PD-L1 expression in AML. Silencing of MUC1 in AML cell lines suppressed PD-L1 expression without a decrease in PD-L1 mRNA levels, suggesting a post-transcriptional mechanism of regulation. We identified the microRNAs miR-200c and miR-34a as key regulators of PD-L1 expression in AML. Silencing of MUC1 in AML cells led to a marked increase in miR-200c and miR-34a levels, without changes in precursor microRNA, suggesting that MUC1 might regulate microRNA-processing. MUC1 signaling decreased the expression of the microRNA-processing protein DICER, via the suppression of c-Jun activity. NanoString (Seattle, WA, USA) array of MUC1-silenced AML cells demonstrated an increase in the majority of probed microRNAs. In an immunocompetent murine AML model, targeting of MUC1 led to a significant increase in leukemia-specific T cells. In concert, targeting MUC1 signaling in human AML cells resulted in enhanced sensitivity to T-cell-mediated lysis. These findings suggest MUC1 is a critical regulator of PD-L1 expression via its effects on microRNA levels and represents a potential therapeutic target to enhance anti-tumor immunity.

Influence of cooling rates and addition of Equex pasta on cooled and frozen-thawed semen of generic gray (Canis lupus) and Mexican gray wolves (C. l. baileyi).

A current priority for the preservation of the endangered Mexican gray wolf (Canis lupus baileyi) is the development of a sperm-based genome resource bank for subsequent use in artificial insemination. To optimize the quality of cryopreserved sperm, the procedures involved in processing semen before and during freezing need to be improved. The aim of this study were to examine the effects of: (i) different cooling periods before freezing and (ii) addition of Equex pasta (Minitüb, Tübingen, Germany) on the characteristics of sperm from the generic gray wolf and the Mexican gray wolf after cooling and cryopreservation. For Mexican wolf sperm, cooling for 0.5 and 1.0 h had a less detrimental effect on cell morphology than cooling for 2.5 h, whereas the slower cooling rate (2.5 h) had a less detrimental effect on functional parameters and seemed to cause less damage to plasma membrane and acrosome integrity than 0.5 and 1.0 h. For the generic gray wolf, cooling semen for 2.5 h had less detrimental effect on plasma membrane integrity and viability; together with the 0.5 h cooling time, it yielded the highest percentages of intact acrosomes. As previously shown in the domestic dog, Equex pasta had no beneficial effect on sperm characteristics in either wolf species.

Effects of the dopamine agonist cabergoline on the pulsatile and TRH-induced secretion of prolactin, LH, and testosterone in male beagle dogs.

In the present study, the pulsatile serum profiles of prolactin, LH and testosterone were investigated in eight clinically healthy fertile male beagles of one to six years of age. Serum hormone concentrations were determined in blood samples collected at 15 min intervals over a period of 6 h before (control) and six days before the end of a four weeks treatment with the dopamine agonist cabergoline (5 microg kg(-1) bodyweight/day). In addition, the effect of cabergoline administration was investigated on thyrotropin-releasing hormone (TRH)-induced changes in the serum concentrations of these hormones. In all eight dogs, the serum prolactin concentrations (mean 3.0 +/- 0.3 ng ml(-1)) were on a relatively constant level not showing any pulsatility, while the secretion patterns of LH and testosterone were characterised by several hormone pulses. Cabergoline administration caused a minor but significant reduction of the mean prolactin concentration (2.9 +/- 0.2 ng ml(-1), p < 0.05) and did not affect the secretion of LH (mean 4.6 +/- 1.3 ng ml(-1) versus 4.4 +/- 1.7 ng ml(-1)) or testosterone (2.5 +/- 0.9 ng ml(-1) versus 2.4 +/- 1.2 ng ml(-1)). Under control conditions, a significant prolactin release was induced by intravenous TRH administration (before TRH: 3.8 +/- 0.9 ng ml(-1), 20 min after TRH: 9.1 +/- 5.9 ng ml(-1)) demonstrating the role of TRH as potent prolactin releasing factor. This prolactin increase was almost completely suppressed under cabergoline medication (before TRH: 3.0 +/- 0.2 ng ml(-1), 20 min after TRH: 3.3 +/- 0.5 ng ml(-1)). The concentrations of LH and testosterone were not affected by TRH administration. The results of these studies suggest that dopamine agonists mainly affect suprabasal secretion of prolactin in the dog.

Morphology of canine placental sites after induced embryonic or fetal death.

Although spontaneous and medically induced canine embryonic or fetal death and "resorption" are clinically well documented, morphological studies of these processes are still missing. The objective of this study was therefore a detailed morphological investigation of canine placental sites after embryonic or fetal death. In five pregnant beagle bitches, embryonic or fetal death was induced by cloprostenol and cabergoline or by aglepristone. Two dogs served as untreated controls. Between Days 30 and 33 of gestation, the bitches were ovariohysterectomized, placental sites were fixed and examined by different methods. Morphological features of placental sites after both treatments were similar, finally leading to a complete disappearance of the placental labyrinth. Although there was an increase in the number of cells in the glandular chambers (superficial endometrial glands) expressing lysozyme after induced fetal death, signs of phagocytosis were absent in these cells, and no increased infiltration of maternal stroma by macrophages (compared to normal placental sites at the same time of gestation) occurred. We inferred that fetal and placental tissues were lysed, but no phagocytosis by genuine or "functional" macrophages was detectable. Further investigations are needed for a more detailed understanding of the morphological processes occurring after embryonic or fetal death in the dog.